Improvement in centrifugal pumps



` it immediately tio-operates,

,viding and UNITED STATES PATENT OFFICE.

IMPROVEMENT lN CENTRQFUGAL PUMPS Specification forming part ot Letters Patent No. 21,756, dated October 12, 1858. i

To a/ZZ whom if; muy concern.-

Be itfknown that I, WILLIAM C. IIIBBARD, of West Roxbury, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvement-s in Centrifugal Pumps for Raising and Forcing IVater and other Fluids; and I do 'hereby declare that the following is a full, clear, and exact description of the principles and construction of the same, taken in connection with the accompanying drawings, making part of this speclication, in which- Figure 1 is .a side elevation; Fig. 2,21 transversev section through the center, and Fig. 3 an elevation of the fan-Wheel, shown separately to show more clearly the form and nrrangement of the Yanes.

The subject-matter of my invention consists of certain improvements inthe centrifugal pump by inea-ns of which the efficiency of its action is much increased as compared with the modes of Construction heretofore in use.

My first improvement relates to the manner of forming the fan-wheel and parts with which so as to receive the water at the inlet and deflect it radially on all sides from the center to the inner ex* trcmiiies of the Yanes without imparting to 1t a rotary motion, in connection with such other construction of its part-s as will impart to the water in passing through the pump the least rotative movement that will do the work. When the lift of the water is small, a small centrifugal force only is required to be gcncrated to overcome it, while the volume of water thrown should be proportionallylarge, so as to usefully employ the whole motive power, and when thelit't is greater the amount of rotation to be imparted to the witter to gen crate the requisite centrifugal force 'to o\er come it must also be correspondingly greater. To adapt the pump to work with the best etect under these varying conditions is the object of my first improvement. To etect this I construct the fan-wheel vwith a curved guide plat-e of the form shownin section in the drnwwhich has a central pointed boss for diings,

deilecting the intlowing current,

lso as'to send it radially outward on ally sides, and which also forms oneside of the chamber through which thcwater nous, the outcr portmi being so formed as in connection with the opposite side of the chamber to give a passage of such circumferential arenas will give an equable flow radially to the water in passing through it. To this plat-e the vnnes of a curved and tapering forni, as shown, are attached hy one edge, their inner extremities being outside of the central inlet, leaving at the center a free open space with nothing to impart any rotative movement to the water. The manner of forming the vanes so as to act upon the water in the' manner before melitioned will be hereinafter more fully described.

My second-improvement relates to the employing usefully of the power or vis r1' vu which remains in the- Water after. it has passed the pump; and it consists in causing the water `to pass through whatl term un expandingoub let, or forming the outlet or discharging passage with a gradually-increasi g area,which is represented in one form in t 1e drawings us attached to the scroll-pipe, which surrounds the fan-wheel and accumulates the discharged fluid, and in another form by the red lines as surrounding the fan-wheel and immediately receiving 'the discharge from it, 'by which means the Velocity of the water may be rcduced to any required degree,the'momentum of the water hy suc-h a. reduction of velocity having a tendency to produce a vacuum bchind, which correspondingly assists the action of the pump. l My third improvement relates to the manner of constructing the casing of the pump, so as to give greater convenience in getting access to 'the operative parts without disturbing the main body of the casing and disconnecting the pipes; and it consists in malting the side of the chamber rin which the fanwheel works with aseparate cover slittle lurger than 'the fan-wheel, so't-hut by simply removing the cover the entire operative parts .et the pump can hc removed without diffi- .culti The description ot' thc lows, the letters referring to'the in all the figures.

A is the main casing of the pump, made with a spiral pipe surrouudingthc fan-Wheel, which has n constantlyducrensing transverse tiren from the small end toward the outlet l corresponding to the accumulating volume or i rfi-iter received .from the anwrheel, so that' its l circumferential velocity shall be the same (n machine is as fol same parts l'the 'curve ofthe vane at itsl inner extremity a 'of 'the water and the other place when the discharge is what is assumed in/the calculation as a maximum. Thisjis 'sent the radial velocity of thewater, a c the v *Y the`radial velocity of the water;

' locity of the Water, and f i Ithe diagonal of the v rectangle c j' h fi.

p slderable.

all parts when the pump is discharging a` quant-ily as small as a maximum in calculatl ing vthe capacity of the-pump.

l; is the fan-wheel. 'It is made witnaguiding-plate of the form shown in section in -Fig. 2t-l1e-part at its center in connection with the shaft` I forming a pointed boss which divides and defleets the water outward on a'll sides to the vanes C, and is continued beyond, forming one side of the passage to the outer extremity of the fvanes, as is Ashown Ain Ithe drawings. To this plate'the vanes C are attached by one edge, which forms their support without any-other.connection with the shaft. The vanes are made tapering to fit the form of the chamber, and are also curved in the direction of theirlengthand set on the plate in 'al manner to be described. In practice I make tangent tothe-diagonal of a rectangle one side of which represents the radial velocity of the water and the otherside the circumferential Gvelocity of the'vane, and at the outer extremity a tangent to the' diagonal of Aa 'rectangle one side of which represents the radial velocity sideA the circumferential velocity of the vane less the `cir.- cumferential velocity of lthe water atthat shownby the paralellograms and diagonals shown 1n' red lines in'Fig. 4' where a b repre-l circumferential velocit-y of the vane at its in-v ner vend, and a (Z the diagonal of samerand c f y, the cirvelocity of the vane at its out-ei" and g 71, thecircumferential vecumferential extremity,

ej f j are' radii, to which the diagonals are ltangents, and which are also radii of the curve -of the vane e f. The inner ends of the vanes. are placedV just exterior to theAinlet-passage through the` vcover D, so that it Vleaves a eentral space for the water entirely unobstructed. The cover I) 'is fitted to receive the suctionpipe Eat i'ts'central orifice, and at its circum- .ferenee is bolted to the casing A, as shown. ,F is the other cover bolted in the same manner to the casing, and at its conte-r is provided with a suitable boss to receive the bearing for the shaftand`also the'stufiing-boxll.

The openings at cach sid'e'of the casing, te which the covers are bolt-ed, are a litt-le larger than -the fan-whecl, as is shown, so that it can be removed fromthe chamber with the cover, and the covers can also be used on either side of the casing, so that the pump can be fitted up to receive the water on either lside,as desired. Upon the shaft I andcxterior to the boss of the co'ver F, a collar Gis fixed to resist the tendency of the fan-whecl to move toward the inlet when the lift is cony .and also that of the main bearing.

-'l`he thrust is taken upon a series ofr'washers m, interposed between the collar and cover, which washers are made of steel and composition alternately....' These are inclosed in an oil-casing,` as shown, which insures their perfect lubrication at all times .l is a con-ical pipe attached to the outlet ot the casing', having'its larger end outward by means et' theconstantlycnlargingarea of' which the water' ,is retarded' in velocity to any required degree, by which means the 'vis rim of .thcfwater given up is made to assist in moving the column of. water behindltcpd is thus usefully employed instead of 'being'.v allowed 'to go to waste, as in theusual manA ner. ',lheincreaseof area in the outlet should be so gradual asv to prevent theI formation of eddics,'a1`1d to cause all parts of the column atany given crossfsection to move with sen! Si bl y the same velocity.V

\Vhen the axis of the pump is placed ver-Y Y tical, as might be the ease in drawing with a .low lift, and the discharge is made into a freesu rroun ding space, I propose tomak'e the' expanding outlet of the form shown in Fig. 2 lin redglines, in which case the scroll-pipe ishot'used.

In theoperation of the pump the before.-l deseribed improvements are intended to produce three particular results, namely: first, to ypresent the water to the varies' without rotatiomand consequen-thravith its maximum of inertia; second, toimpart tolhe'water the least` amount of power that will do the work;

and, third, toabstraet from the water after itez; passes the pump the power that remains 1n it and which otherwise would, be wasted, and

make-it assist 'in the operation.

NVhat I claim as my invention is as follows: j j

1. vIn the construction of the fanwh'eel, the

combination of the curved guide-plate B with the vanes C, arrangeclaround a central open space, substantially as described, and working in v connection with the covers D and F,-

rand casing A, or such other equivalent dey rwiees as will co-operate with it upon the'. samer.

principle. i

, 2. l do not clannthe spiral passage of cmscliarge yconstantly enlarging toward its exit to're'ccive the accumulated discharge from the tan-wheel, as that has before been used, but in combination with the centrifugal pump I claim the expanding o u tiet, constructed upon the principle described, whether employed in combination with the spiral passage of 'discharge or applied directly to. the fan-wheel, substantially as described. l f

Constructing the casing of a centrifugal pump with a detached cover F, in combina- Lion with the fan-wheel and lixed casing, s'ul'istantialiy as described.

.llostom July 1, 1858.

' WM. C. HIBBARD Witnesses: v

JOHN H. ToMLlNsoN, H.. A. Pannen. 'Y 

